The nominal that is attached to the handler/fee earner might be invalid due to been deleted or closed, the steps to check are below:
Select Handler Maintenance, find the relevant fee earner in the handler list.
Select the Practice tab at the bottom of the screen.
Check the Profit Code is linked correctly on the correct practice.
Go into Nominal Maintenance and search for the nominal code from Handler Maintenance.
Check the nominal is not closed by highlighting the nominal and checking the closed tick box is empty.
Untick the box if the nominal is closed.
If no nominal is present then a new nominal needs creating:
Open Nominal Maintenance, click New at the bottom of the screen.
The nominal should be set up the same as the other fee income nominals.
Once the nominal is created then go into Accounts Administration (password needed Admin user should have this)
Select the Short Code tab, select New .
Add the nominal and the name of the fee earner into the short code and select SAVE.
Select Handler Maintenance and select correct fee earner on the left hand side, click update.
Select the Practice tab,
Click on Profit Code and select the new short code you have added.
If the above are all correct it might just be the WIP on the bill hasn't got a nominal selected against it:
Go into Slip Posting and select to AMEND on the specific slip.
Select the grid button where it says Click to Allocate Fees.
Select VIEW WIP & SET NOMINALS.
Find the fee earner and select on the Profit Costs Nominal the correct profit code for the fee earner.